Optical-NIR Multi-band Photometric Analysis and Characterization of Giant Exoplanets with CPI-C
Abstract
We present a multi-band photometric approach to characterize giant exoplanets, which represents one of the anticipated core scientific outcomes of Cool Planet Imaging Coronagraph (CPI-C). CPI-C operates with two observational channels covering visible and near-infrared wavelengths, each equipped with four broadband filters. The planet--star flux ratio integrated over each filter bandpass is calculated for photometric analysis. For cool planets observed in the visible bands, the data are primarily used to fit the overall spectral shape and methane-induced modulation, providing sensitivity to metallicity- and cloud-dependent spectral variations while constraining the reflected-light spectral shape and the combined scaling involving planet radius, orbital separation, and orbital phase. In the near-infrared bands, which probe thermal emission, the data help to better constrain fundamental planetary parameters including the effective temperature, radius, surface gravity and mass. For a synthetic giant planet with measurable reflected-light and thermal-emission components, the combined VIS4+NIR4 data provide tighter same-target constraints than either filter set alone, especially for the planet radius and cloud sedimentation parameter. Our simulations incorporate realistic instrument throughput, detector noise, and residual speckle noise. The results demonstrate that the eight-band design spanning visible to near-infrared wavelengths supports reflected-light diagnostics, thermal-emission characterization, and joint optical--NIR analysis of giant exoplanets within CPI-C science observations.
Versions
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BibTeX
@misc{zhu2026opticalnir,
title = {{Optical-NIR Multi-band Photometric Analysis and Characterization of Giant Exoplanets with CPI-C}},
author = {Yiming Zhu and Gang Zhao and Xi Zhang and Gang Wang and Bingli Niu and Zhonghua Lv and Jiangpei Dou},
howpublished = {arXiv},
year = {2026},
month = aug,
doi = {10.48550/arxiv.2608.16215},
eprint = {2608.16215},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2608.16215},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Optical-NIR Multi-band Photometric Analysis and Characterization of Giant Exoplanets with CPI-C
AU - Yiming Zhu
AU - Gang Zhao
AU - Xi Zhang
AU - Gang Wang
AU - Bingli Niu
AU - Zhonghua Lv
AU - Jiangpei Dou
PY - 2026
DA - 2026/08/17
PB - arXiv
DO - 10.48550/arxiv.2608.16215
UR - https://arxiv.org/abs/2608.16215
AB - We present a multi-band photometric approach to characterize giant exoplanets, which represents one of the anticipated core scientific outcomes of Cool Planet Imaging Coronagraph (CPI-C). CPI-C operates with two observational channels covering visible and near-infrared wavelengths, each equipped with four broadband filters. The planet--star flux ratio integrated over each filter bandpass is calculated for photometric analysis. For cool planets observed in the visible bands, the data are primarily used to fit the overall spectral shape and methane-induced modulation, providing sensitivity to metallicity- and cloud-dependent spectral variations while constraining the reflected-light spectral shape and the combined scaling involving planet radius, orbital separation, and orbital phase. In the near-infrared bands, which probe thermal emission, the data help to better constrain fundamental planetary parameters including the effective temperature, radius, surface gravity and mass. For a synthetic giant planet with measurable reflected-light and thermal-emission components, the combined VIS4+NIR4 data provide tighter same-target constraints than either filter set alone, especially for the planet radius and cloud sedimentation parameter. Our simulations incorporate realistic instrument throughput, detector noise, and residual speckle noise. The results demonstrate that the eight-band design spanning visible to near-infrared wavelengths supports reflected-light diagnostics, thermal-emission characterization, and joint optical--NIR analysis of giant exoplanets within CPI-C science observations.
ER -